Leak-resistant paper clamshell containers

ABSTRACT

Blanks for forming clamshell containers and the resulting clamshell containers are described. The clamshell containers include a tray and a lid that are hingedly connected together. The tray is liquid tight, and typically includes gussets on each corner to prevent leakage. The lid and tray can be locked via at least one locking mechanism, optionally two different locking mechanisms. A first locking mechanism involves a front panel on the tray, with an extension portion that terminates in a hook or tab. The extension portion can fold over the front panel of the lid, and the hook or tabs slide into a slit(s) on the top of the lid. An optional second locking mechanism involves lid detents and tray detents. In some embodiments, in the locked position, the lid detents are underneath the tray detents and the tray detents retain the lid detents in place until a force is applied.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to PCT Application No.PCT/US2019/052447 filed on Sep. 23, 2019 and U.S. Application No.62/734,904, filed Sep. 21, 2018, the disclosures of which areincorporated herein by reference in their entirety.

FIELD OF THE INVENTION

This invention generally relates to containers for storing andtransporting food.

BACKGROUND OF THE INVENTION

Various containers are used to store and transport food, particularly inthe “take-out” food industry. Food storage containers are typicallyformed by mating a lid with a base. Preferred materials include paperand plastics. Many different containers have been designed to preventleakage of fluids during travel and prevent or reduce spoilage of foods.However, many of these containers are made from styrofoam and othernon-degradable materials.

There is a need for improved containers for food storage andtransportation. Particularly, there is a need for containers that areable to secure the food inside the container prior to use and preventearly or inadvertent opening of the container. There is also a need forimproved food storage containers that are made from easily degraded orrecycled materials, such as paperboard, which also prevent or reduceleakage of liquids or sauces that are stored in the containers.

SUMMARY OF THE INVENTION

Blanks formed from paperboard for forming clamshell containers and theresulting clamshell containers are described herein. The clamshellcontainers include a tray and a lid that are hingedly connectedtogether, such that the lid can be closed over the tray to enclose foodtherein, or opened to allow access to and removal of the food from thetray. The tray is leak-resistant.

The lid and tray are able to be secured in the closed position via oneor more locking mechanisms. The container includes at least one lockingmechanism, and optionally includes two or more locking mechanisms.

A first locking mechanism involves a front panel on the tray, whichincludes a panel extension portion that terminates in a tab closuremechanism. The extension portion folds over the front panel of the lid,and the tab(s) slide into a slit on the top of the lid such that thecontainer is in its closed and locked position.

The tray is liquid tight and typically includes gussets on each cornerto prevent leakage. The gussets can attach to the side panels of thetray or to the front panel and rear panel of the tray.

Optionally, the container includes a second locking mechanism. Thesecond locking mechanism typically involves lid detents and traydetents. In some embodiments, the lid detents and tray detents aresubstantially perpendicular to each other. In the locked position, thelid detents are underneath the tray detents and the tray detents securethe lid detents in place until a force is applied to separate them. Inother embodiments, the lid detents and the tray detents are alignedsubstantially parallel to each other and configured to contact andinterlock such that one pair of detents lies on top of the other pair ofdetents in the locked position.

BRIEF DESCRIPTION OF THE DRAWINGS

Unless otherwise stated, within the borders of an illustration of ablank, dashed lines indicate fold lines or other lines of weakness andsolid lines indicate borders flaps of the blank.

Unless otherwise stated, with respect to illustrations of the assembledcontainer, solid lines indicate fold lines, score lines, perforationlines, or other lines of weakness.

FIG. 1 is a plan view of an exemplary blank configured to form aclamshell container with a lid and a tray, where the tray has arectangular bottom panel and the lid has a rectangular top panel.

FIG. 2A is a partial plan views of an alternative configuration forfront corners on the front tray panel of the blank depicted in FIG. 1 ,where the resulting gusset has a double layer tray detent. FIG. 2Bdepicts a modification of the partial plan view of the front tray panelof FIG. 2A, where the modification is a zipper with pull-tabs at eachend in the extension portion. FIG. 2C depicts a modification of thepartial plan view of the front tray panel of FIG. 2A, where themodification is a zipper in the extension portion.

FIG. 3 is a plan view of an exemplary blank configured to form aclamshell container with a lid and a tray, where the tray has asquare-shaped bottom panel and the lid has a square-shaped top panel.

FIGS. 4A-4C are perspective views of a container assembled from theblank depicted in FIG. 3 in the open (FIG. 4A) and closed positions(FIGS. 4B and 4C). FIG. 4C shows the container in the closed and lockedposition.

FIGS. 5A-5C are various views of the clamshell container that forms whenthe blank depicted in FIG. 1 is assembled (however, it contains adifferent hook configuration, which faces the opposite directioncompared to the hook depicted in the blank of FIG. 1 ). FIG. 5A depictsthe container in the open position; FIG. 5B depicts a front view of thecontainer in the closed and locked position; FIG. 5C depicts a rear viewof the container in the closed and locked position.

FIGS. 6A-6C are various views of the clamshell container that forms whenthe blank depicted in FIG. 1 with a modification of the gussets as shownin FIG. 2A is assembled. When the clamshell container is assembled, thetray detents are double ply and the corresponding gussets are attachedto the front panel. FIG. 6A depicts the container in the open position;FIG. 6B depicts a front view of the container in the closed and lockedposition; FIG. 6C depicts a rear view of the container in the closed andlocked position.

FIGS. 7A and 7B are two views of the clamshell container that forms whenthe blank depicted in FIG. 3 is assembled (however a different lockingmechanism is depicted in FIGS. 7A and 7B). FIG. 7A depicts the containerin the closed position with only the detents in the locked position;FIG. 7B depicts a front view of the container in the closed positionwith both the detents and the hook tab that extends from the front panelin the locked position.

FIGS. 8A and 8B are partial plan views of blanks with two variations forthe corners that form gussets on the tray portion of the clamshellcontainer. FIG. 8A depicts a blank with a cut out portion in one of thegusset panels and an emboss slug in a proximal portion of the adjacentside panel, which is assembled to form a gusset that adheres to theoutside of the adjacent side panel. FIG. 8B depicts a blank with a cutout portion in the opposite one of the gusset panels (compared to FIG.8A) and an emboss slug in a portion of the adjacent side panel, which isassembled to form a gusset that adheres to the outside of the adjacentside panel. FIGS. 8C-8E show the relative positions of the portions thatfold together to form the gusset corner. FIG. 8C shows the blank. FIG.8D shows the blank of FIG. 8C in a partially folded position. FIG. 8Eshows the fully assembled gusset corner form the inside view.

FIGS. 9A-9F show blanks for forming a square clamshell container withdifferent closing mechanisms. FIG. 9A shows two tabs attached to arectangular shaped extension portion configured to fit in two slits onthe top panel of the lid. FIG. 9B shows a left hook attached to arectangular shaped extension portion configured to fit in a curved sliton the top panel of the lid. FIG. 9C shows a right hook attached to atriangular shaped extension portion configured to fit in a curved sliton the top panel of the lid. FIG. 9D shows a left hook attached to atriangular shaped extension portion configured to fit in a curved sliton the top panel of the lid. FIG. 9E shows a two-sided hook attached toa triangular shaped extension portion configured to fit in a curved sliton the top panel of the lid, where the left hook is attached to theright hook via a curved connecting portion. FIG. 9F shows a tab with twoflaps attached to a triangular shaped extension portion configured tofit in a curved slit on the top panel of the lid.

FIGS. 10A-10E show assembled views of the blanks of FIGS. 9C-9F,respectively. FIGS. 10A and 10B show the container formed by the blankof FIG. 9F in the closed and locked (FIG. 10A) and closed and unlocked(FIG. 10B) positions. FIG. 10C shows the container formed by the blankof FIG. 9C in the closed and unlocked position. FIG. 10D shows thecontainer formed by the blank of FIG. 9D in the closed and unlockedposition. FIG. 10E shows the container formed by the blank of FIG. 9E inthe closed and unlocked position.

FIGS. 11A-11C show perspective views of a container with an extensionportion, tab and slit for a locking mechanism, without a detent-basedlocking mechanism. The container is shown in the open position (FIG.11A), the closed and locked position (FIG. 11B), and closed and unlockedposition (FIG. 11C).

FIGS. 12A and 12B show front (FIG. 12A) and rear (FIG. 12B) views of acontainer with a window in the rear lid panel.

FIG. 13 shows a plan view of a blank for forming a container with asquare lid and square tray with a window in the top and rear lid panels.

FIG. 14 shows a plan view of a blank for forming a container with asquare lid and square tray with a window in the top lid panel.

FIG. 15 is a plan view of an exemplary blank configured to form aclamshell container with a lid and a tray, where the tray has arectangular bottom panel and corresponding tray detents, and the lid hasa rectangular top panel and corresponding lid detents.

FIG. 16 is a plan view of an exemplary blank configured to form aclamshell container with a lid and a tray, where the tray has arectangular bottom panel and corresponding tray detents, the lid has arectangular top panel and corresponding lid detents, and the fold lineconnecting the lid portion and tray portion has two pairs of reliefcuts.

FIG. 17A-17C are perspective views of the clamshell container that formswhen the blank depicted in FIG. 15 is assembled. FIG. 17A depicts thecontainer in the open position; FIG. 17B depicts the container in aclosed position. FIG. 17C depicts the container in the closed and lockedposition.

FIG. 18 is a plan view of an exemplary blank configured to form aclamshell container with a lid, a tray, and a locking mechanism, wherethe tray has a rectangular bottom panel, and the lid has a rectangulartop panel. The locking mechanism contains a belt formed by an extensionportion attached to the tray that terminates in a tab, which isinsertable into a slit in the top panel of the lid when the container isassembled.

FIGS. 19A-19C are various views of the clamshell container that formswhen the blank depicted in FIG. 18 is assembled. FIG. 19A depicts thecontainer in the open position; FIG. 19B depicts a front view of thecontainer in the closed and locked position; FIG. 19C depicts a rearview of the container in the closed and locked position.

FIG. 20 is a plan view of an exemplary blank configured to form aclamshell container with a lid, a tray, and a locking mechanism, wherethe tray has a square-shaped bottom panel and the lid has asquare-shaped top panel. The locking mechanism contains a belt formed byan extension portion attached to the tray that terminates in a tab,which is insertable into a slit in the top panel of the lid when thecontainer is assembled.

FIGS. 21A-21C are perspective views of a container assembled from theblank depicted in FIG. 20 in the open (FIG. 21A) and closed positions(FIGS. 21B and 21C). FIG. 21C shows the container in the closed andlocked position.

FIGS. 22A and 22B are two views of the clamshell container that formswhen the blank depicted in FIG. 20 is assembled (however a hook tab forlocking is depicted in FIGS. 22A and 22B). FIG. 22A depicts thecontainer in the closed position; FIG. 22B depicts a front view of thecontainer in the closed position with the hook tab that extends from thefront panel of the tray in the locked position.

FIGS. 23A-23D show exemplary blanks for forming a square clamshellcontainer with different tab and slit shapes for the locking mechanism.FIG. 23A shows two tabs attached to a rectangular shaped extensionportion configured to fit in two slits on the top panel of the lid. FIG.23B shows a left hook attached to a rectangular shaped extension portionconfigured to fit in a curved slit on the top panel of the lid. FIG. 23Cshows a right hook attached to a triangular shaped extension portionconfigured to fit in a curved slit on the top panel of the lid. FIG. 23Dshows a left hook attached to a triangular shaped extension portionconfigured to fit in a curved slit on the top panel of the lid.

FIGS. 24A and 24B show the container formed by the blank of FIG. 23C inthe closed and locked (FIG. 24A) and closed and unlocked (FIG. 24B)positions (however it contains a different shaped tab with two flapsattached to a triangular shaped extension portion configured to fit in acurved slit on the top panel of the lid is depicted in FIGS. 24A and 24Bcompared to the tab depicted in the blank of FIG. 23C). FIG. 24C showsthe container formed by the blank of FIG. 23C in the closed and unlockedposition. FIG. 24D shows the container formed by the blank of FIG. 23Din the closed and unlocked position. FIG. 24E shows the container formedby the blank of FIG. 23C in the closed and unlocked position (however itcontains a differently shaped hook compared to the hook depicted in theblank of FIG. 23C). The hook depicted in FIG. 24E is a two-sided hookattached to a triangular shaped extension portion configured to fit in acurved slit on the top panel of the lid is depicted in FIG. 24E.

FIGS. 25A and 25B show front (FIG. 25A) and rear (FIG. 25B) views of acontainer with a window in the real lid panel. FIG. 25A is a frontperspective view of the container in a partially open position. FIG. 25Bis a rear perspective view of the container in the closed and lockedposition.

FIG. 26 shows a plan view of an exemplary blank for forming a containerwith a square lid and a square tray with a window in the top and rearlid panels, and a locking mechanism. The locking mechanism contains abelt formed by an extension portion attached to the tray that terminatesin a hook, which is insertable into a slit in the top panel of the lidwhen the container is assembled.

FIG. 27 shows a plan view of an exemplary blank for forming a containerwith a square lid and a square tray with a circular window in the toplid panel, and a locking mechanism. The locking mechanism contains abelt formed by an extension portion attached to the tray that terminatesin a tab, which is insertable into a slit in the top panel of the lidwhen the container is assembled.

FIG. 28 is a plan view of an exemplary blank configured to form aclamshell container with a lid, a tray, and a locking mechanism, wherethe tray has a rectangular bottom panel, and the lid has a rectangulartop panel and a recessed front panel. The locking mechanism contains abelt formed by an extension portion attached to the tray that terminatesin a hook, which is insertable into a slit in the top panel of the lidwhen the container is assembled.

FIG. 29 is a plan view of an exemplary blank configured to form aclamshell container with a lid, a tray, and a locking mechanism, wherethe tray has a rectangular bottom panel, and the lid has a rectangulartop panel and a recessed front panel. The locking mechanism contains abelt formed by a triangular shaped extension portion attached to thetray that terminates in a tab containing two flaps, which is able toinsert into a slit in the top panel of the lid, when the container isassembled. The tab has two flaps, which fit into a curved slit on thetop panel of the lid.

FIGS. 30A-30C show the container formed by the blank of FIG. 29 in theopen (FIG. 30A), closed and unlocked (FIG. 30B), and closed and locked(FIG. 30C) positions.

FIGS. 31A-31C are various views of the clamshell container that formswhen the blank depicted in FIG. 1 with a modification of the gussets asshown in FIG. 2B is assembled (however the tabs at each end of thezipper on the extension portion are rounded). When the clamshellcontainer is assembled, the tray detents are double ply and thecorresponding gussets are attached to the front panel. FIG. 31A depictsthe container in the open position; FIG. 31B depicts a front view of thecontainer in the closed and locked position; FIG. 31C depicts a rearview of the container in the closed and locked position.

FIGS. 32A and 32B are two views of the clamshell container that formswhen the blank depicted in FIG. 3 is assembled (however the lockingmechanism is modified as depicted in FIGS. 7A and 7B and the extensionportion on the front tray panel is modified to contain a zipper portionas depicted in FIG. 2B). FIG. 32A depicts the container in the closedposition with only the detents in the locked position; FIG. 32B depictsa front view of the container in the closed position with both thedetents and the hook tab that extends from the front panel in the lockedposition.

DETAILED DESCRIPTION OF THE INVENTION

Paperboard blanks for forming clamshell containers and the resultingclamshell containers are described herein.

I. Assembled Clamshell Container

The clamshell container contains a tray and a lid that are hingedlyconnected together such that the lid can be closed over the tray toenclose food therein, or opened to allow access to and removal of thefood from the tray.

In the closed position, the edge of the front panel of the tray contactsthe inside surface of the upper portion of the front panel of the lid,however the side panels of the lid typically protrude beyond the edge ofthe side panels of the tray. The gap between the lid and the tray allowsfor heat and steam to escape from the closed container, when hot food isenclosed therein.

The lid typically contains a unitary top panel. In contrast to a lunchpail commonly used in take-out for Chinese food, the top of the lid(e.g. the top panel) is not formed from multiple flaps.

The corners of the tray are liquid tight, such as due to the presence ofa gusset in each corner. This prevents or reduces leakage of liquids outof the tray.

The lid and the tray can be locked via a single locking mechanisminvolving a belt that extends from one portion of the clamshellcontainer, such as the tray, and wraps around part of the other portion,such as the lid, and is secured thereto, such as by inserting a tab intoa slot configured to receive and retain the tab.

The lid and the tray can be locked in the closed position via a beltformed of an extension portion that terminates in a tab, which slidesinto a correspondingly shaped slit or slits on another surface of theclosed container. Typically, one or more of the panels (e.g. side orfront) of the tray include an extension portion.

The lid and the tray can be unlocked when a user applies a force to thetab to pull it out of or remove it from the slit or slits. Due to theconfiguration of the tab and the slit, the user may need to apply forcein two directions to remove the tab without breaking it. Optionally, thetab breaks when force is applied, such as in a single direction, and thecontainer is unlocked. Optionally, the front and/or the rear of the lidor the tray contains two or more perforated lines, preferably the lid orthe tray contains two perforated parallel line(s) that define a zipperregion, to allow for easy opening and optionally removal of the lid fromthe tray. Typically, the zipper region on the lid and/or tray is locatedabove the corners of the tray. For example, a zipper region is locatedon the extension portion of the front tray panel, in the regionconnecting the extension portion and the tab (“connecting region”),and/or on the rear lid panel. Optionally, one pull-tab is located on atleast one of the ends, optionally on both of the ends of the zipperregion. For example, the zipper can be located on the extension portionof the front tray panel, in the connecting region, and/or the rear lidpanel of the container. The incorporation of a zipper can facilitate theopening of the locked container. For example, a user can remove thezipper located on the front tray panel of the locked container and thusopen the container to provide easy access to the contents within thecontainer. If at least one tab is present on the end of the zipperportion, the user can pull the tab to remove the zipper and thereby openthe lid to access the food located inside the container.

Optionally, the lid or the tray contains only one perforated line on thefront and/or the rear of the container to allow easy opening of the lidfrom the tray. The perforated line can be located anywhere on theextension portion, at the fold line connecting the extension portion andthe tab, at the fold line connecting the extension portion and the fronttray panel, in the connecting region, anywhere on the rear lid panel,and/or at the fold line connecting the rear tray panel and the rear lidpanel. For example, the perforated line is located on the extensionportion. The user can apply a single direction force on the perforatedline (e.g. push open the perforated line) to separate the tray from thetab and thus open the container.

Optionally, the container includes a single perforated line or a zipperon the front of the container and a single perforated line or a zipperon the rear of the container, to allow for removal of the lid from thetray.

The tray can contain an extension portion that extends from the top ofthe front tray panel beyond the height of the side tray panels, when thetray is assembled. The extension portion terminates in a tab of anysuitable shape, such as a hook tab or tuck tabs, which fit in a slit onthe top panel of the lid to secure the container in the closed position.Optionally, one or two perforated lines, preferably two perforatedparallel lines are located on the extension portion to allow for easyopening of the container from its locked position. When two perforatedparallel lines are located on the extension portion, they form a zipperregion on the front tray panel.

Generally, neither the lid nor the tray contains a peripheral flangethat projects outwardly from the lid and/or tray. Typically, both thelid and the tray do not contain flanges that project outwardly from thelip of the lid and project outwardly from the tray portion and alignsuch that they overlap with each other.

a. Tray

The tray forms the bottom of the container. The tray is generallyleak-resistant. The tray can have any suitable shape and dimensions, butgenerally corresponds with the shape and dimensions of the lid so thatthey are able to close and lock in the closed position.

The tray generally has a substantially trapezoidal shape formed from arectangular bottom panel and two substantially upstanding pairs ofopposing tray panels, which correspond with four pairs of adjacent traypanels. Each of the tray panels is attached to one side of the bottompanel and protrudes upwards from the bottom panel. Each pair of adjacenttray panels is hingedly connected in a liquid tight manner with a foldedgusset that is unitary with each of the adjacent tray panels in thepair. The gusset is secured by an adhesive to the exterior surface ofone of the side panels in the pair. Optionally, the gusset can be insidethe tray and secured by an adhesive to an interior surface of one of theside panels in the pair.

One pair of opposing tray panels forms the front tray panel and the reartray panel. The rear tray panel is hingedly attached via a fold line tothe rear lid panel.

The other pair of opposing tray panels forms the two opposing side traypanels.

The front tray panel is optionally taller than the other panels in thetray. The front tray panel typically includes an extension portion,which extends beyond the height of the side tray panels, when the trayis assembled. The extension portion is foldably connected to the frontpanel along a fold line. The extension portion terminates in one or moretabs, such as a tuck tab or hook tab, that mates with a correspondingslit on the top panel of the lid. The extension portion can have anysuitable size and shape that allows the tab located at its end to beinserted into the slit located in the top panel of the lid. In someembodiments, the extension portion has a substantially triangular shape.In other embodiments, the extension portion has a substantiallyrectangular shape. One or more fold lines typically connect the tab tothe extension portion. When in the closed and locked position, theextension portion lays in front of the front lid panel, and bends alongthe fold line, allowing the tab to lay on top of the top panel of thelid and be inserted into the slit on the top panel.

In some embodiments, the height (H_(e)) of the extension portion of thetray is substantially the same as or similar to the height (H_(L)) ofthe lid front panel. The height of the extension portion is the distancefrom the fold line between the front tray panel and the extensionportion to a fold line between the tab and the extension portion. (see,e.g. FIG. 15 , H_(e) is the distance between fold line 313″ and foldline 315″).

Optionally, the height of the extension portion is smaller than theheight of the front lid panel. Typically this relationship is presentwhen the lid and tray include interlocking detents, which lock in amanner that pulls the lid downward so that the lid detents are below thecorresponding tray detents.

i. Gusset Corners

Each gusset comprises a pair of gusset panels, containing a first gussetpanel and a second gusset panel, separated by a fold line. Optionally,one gusset panel includes a slot or opening, which facilitates adheringthe gusset to the exterior surface of one of the side panels, the frontpanel, or the rear panel.

ii. Tray Detents

Optionally, the tray includes a pair of detents. In some embodiments,the pair of tray detents protrude either beyond the plane of the fronttray panel and from the end of each side wall or beyond the plane of therespective side wall and from each end of the front tray panel. In someembodiments, the pair of tray detents includes one detent located oneach corner of an extension portion of the front tray panel, generallylocated at the bottom of the extension portion. In this embodiment, thelid contains a second pair of detents on the front lid panel that are inthe same plane as the front lid panel and align with the first pair ofdetents. The lid and the tray detents are configured to contact eachother when the container is in the closed position, such that the traydetents mate with the lid detents and lock the front lid panel and trayfront panel together. In the locked position, the lid detents are in afirst plane and tray detents are in a second plane where the first andsecond planes intersect at an acute angle that is less than 90°,typically less than 30°, less than 20°, less than 10°, and optionallybetween 0° and 5°, or between 0° and 10°, or smaller than 5°.

b. Lid

The lid forms the top of the container. The lid can have any suitableshape and dimensions, but generally corresponds with the shape anddimensions of the tray so that they are able to close and lock in theclosed position. The lid generally has a substantially trapezoidal shapeformed from a rectangular top panel and two pairs of opposing lidpanels, which correspond with four pairs of adjacent lid panels. Each ofthe lid panels is attached to one side of the top panel and protrudesdownwards from the top panel. The top panel can be substantially flat orcurved, forming a lid with a dome-shape. Each pair of adjacent lidpanels is connected to its adjacent lid panel via a glue tab, which isunitary with one of the lid panels and secured by an adhesive to theother of the lid panels in the pair. The glue tab is secured by anadhesive to the interior surface of one of the side panels in the pair.

One pair of opposing lid panels forms the front lid panel and the rearlid panel. The other pair of opposing lid panels forms the two opposingside lid panels.

The front lid panel is defined by a top edge, two side edges, and alower border. The height of the front lid panel (H_(L)) is the distancefrom the lower border of the front lid panel to top edge (see, e.g. FIG.3 , H_(L) is the distance from the fold line 211′, which forms the topedge when the container is assembled, to the lower border 293′ of thelid front panel).

In some embodiments, the front lid panel includes a recessed portion.The recessed portion can be configured to facilitate alignment of acorresponding extension portion on the tray and/or locking of the lidand the tray in the closed position. In embodiments in which the frontlid panel includes a recessed portion, the front lid panel is defined bya top edge, two side edges, and the recessed portion defined by an upperborder, two side borders, a first portion of the lower border, and asecond portion of the lower border, where each portion of the lowerborder is connected to one of the side borders. Each portion of thelower border is substantially parallel to the upper border. Typicallythe upper and lower borders are straight. The side borders can bestraight or curved.

The top panel of the lid typically includes a slit or slits, which isone component in a locking mechanism. The slit or slits have a suitableshape and size to receive a tab or portions of a tab that is attached tothe tray, and thereby lock the lid and tray together in the closedposition, to aid in transport of the materials, such as food, inside ofthe container.

i. Adhesive

An adhesive secures the gussets to the tray panels and secures the gluetabs to the lid panels. The adhesive that secures the gussets to thetray panels and that secures the glue tabs to the lid panels ispreferably a food grade adhesive. The selection of the particularadhesive placed on the blank during assembly of the container depends onthe capability desired for the carton (e.g. microwavable, oven safeand/or refrigerator safe). Preferably, the adhesive resists melting uponexposure to high temperature and when exposed to microwave or other heatradiation. This allows food to be safely heated in a microwave orconvection oven, and the container to retain its assembledconfiguration. Suitable adhesives include but are not limited to CH-25hot melt adhesive and AP0283WE liquid adhesive.

In some embodiments, the gussets adhere to the tray panels and/or theglue tabs adhere to the lid panels by thermal bonding (e.g. heat seal).Optionally, the gussets adhere to the tray panels by an adhesivedescribed above or by thermal bonding, or a combination thereof, and theglue tabs adhere to the lid panels by an adhesive described above. Forexample, the interior and exterior surfaces of the tray panel is coatedwith a heat sealable coating, such as a food grade heat sealablecoating. Once the gussets are folded to contact an interior or exteriorsurface of the tray panels, the folded gussets adhere to the tray panelby applying heat to the gusset to form bonding between the contactedsurfaces. In some embodiments, the heat sealable coating is only on theinterior surface of the tray panel. In some embodiments, the heatsealable coating is located only on the interior or exterior surface ofthe gussets and the portion of the interior or exterior surface to whichthey adhere.

ii. Recessed Portion

Optionally, the front panel of the lid includes a recessed portion. Therecessed portion is defined by an upper border, two side borders, afirst portion of the lower border, and a second portion of the lowerborder, where each portion of the lower border is connected to one ofthe side borders. Each portion of the lower border is substantiallyparallel to the upper border. Typically the upper and lower borders aregenerally substantially straight. Optionally, the front lid panelcontains two front corners, where each corner is located on one side ofthe recessed portion.

The side borders can be straight or curved. The side borders aretypically mirror images of each other. In some embodiments, each of theside borders is substantially straight and intersects the lower borderat an angle of at least 90°, typically at an angle of greater than 90°.In some embodiments, each of the side borders is curved and protrudesinwardly, extending over a portion of the upper border in the form ofside tabs. If corresponding tray detents are present on the container,these side tabs can function as interlocking lid detents.

For lids that contain a recessed portion, the height of the front lidpanel (H_(L)) can be measured from the upper border of the recessedportion to the top edge of the front lid panel (see, e.g. FIG. 15 ,H_(L) is the distance from fold line 211″ to the upper border 281 of therecessed portion 285).

iii. Lid Detents

Optionally, the lid includes a pair of lid detents. In some embodiments,the pair of detents protrude either beyond the plane of the front lidpanel and from the end of each side wall or beyond the plane of therespective side wall and from each end of the front lid panel. In someembodiments, the pair of lid detents are located in the recessed portionof the front lid panel and protrude from each of the sides, with theirouter border forming each of the side borders.

The lid and the tray detents are configured to contact each other whenthe container is in the closed position, such that the tray detents matewith the lid detents and lock the front lid panel and tray front paneltogether. In some embodiments in the locked position, the lid detentsand tray detents are aligned in planes that intersect at an angle ofless than 90°, such as an angle of less than 45°, typically less than45°, such as less than 30°, less than 20°, such as between greater than0 and 25°, greater than 0° and 20°, greater than 0° and 15°, greaterthan 0° and 10°, greater than 0° and 5°. In some embodiments in thelocked position, the lid detents and tray detents are aligned insubstantially perpendicular planes.

c. Optional Features

i. Opening Forming a Window in Lid and/or Tray

Optionally, the lid and/or tray includes one or more openings thatallows one to view the contents in the interior of the clamshell cartonand/or permit assessment of the food item or items inside the clamshellcarton when the clamshell carton is assembled from the blank and whenthe container is in a closed position. The food item(s) or other item(s)can be disposed directly in the clamshell carton. The opening can becovered by a film, plastic, or other covering made of a transparentmaterial that forms a window to allow the items inside the carton to beviewed or otherwise inspected or assessed therethrough, even when thecontainer is in a closed position. Suitable materials include acetatefilm (e.g. 1 mil. thick), polyester film (e.g. 1 mil. thick), oranti-fog polypropylene film (e.g. 1 mil thick). Depending upon whetherto carton is desired to be microwaveable, oven safe and/or refrigeratorsafe, different materials may be chosen to cover the opening.

The opening can have any suitable shape, size, and configuration. Theopening can be located in a variety of different locations. The openingcan be in a regular shape, such as a rectangle, square, oval, circle,etc. The opening can be in an irregular shape. The opening may belocated in the lid, such as on the top panel (see, e.g. FIG. 14 ,opening 410 and FIG. 27 , opening 410′), on one or both of the side lidpanels, on the front lid panel, and/or on the rear lid panel (see, e.g.FIGS. 12A and 12B, opening 420, and FIGS. 26A and 26B, opening 420′).The opening will generally not be located where a slit is present. Theopening may be located in the tray, such as on the bottom panel, on oneor both of the side tray panels, on the front tray panel, and/or on therear tray panel. In some embodiments, the top panel includes an openingand the rear lid panel and/or front tray panel includes an opening forviewing the contents. FIGS. 13 and 27 show exemplary blanks with asingle opening 430 and 430′ respectively in both the top and rear lidpanels that forms a window in the lid of the resulting container.

Optionally, the opening can contain multiple openings, which can becovered by a single covering or which can be covered by multiplecoverings, or the opening can be a single opening covered by more thanone covering.

ii. Identifying Markings on Lid and/or Tray

Optionally, the lid and/or tray include identifying markings, such as toindicate the direction the container should be placed to preventaccidental spillage of the food contents (e.g. with an arrow or “thisside up” marking). Logos or other decorative or informative markings canalso be included on the lid or tray, as desired.

iii. Vents for Release of Heat and/or Steam

Optionally, one or more panels in the container contain vents to allowheat and steam to escape. The vents can be formed from a single cut,such as illustrated in FIGS. 9A and 9B.

Optionally, the lid and/or tray include relief cuts on the fold lineconnecting the lid portion and tray portion of the container. The reliefcuts allow for heat and steam to escape from the container, when thecontainer is in the closed position and when a hot substance, such ashot food, is enclosed therein.

Generally, the relief cuts may be a single cut located on the rear lidpanel or on the rear tray panel, or multiple cuts located on the rearlid panel and/or on the rear tray panel. In some embodiments, the cutscan be arranged in pairs, i.e. one of the relief cuts is located on therear lid panel and another one is located on the rear tray panel, wherethe pair of cuts meet to form a V-shape centered on the fold line thatconnects the lid portion and the tray portion. In some embodiments, oneof the relief cuts is located on the rear lid panel and another islocated on the rear tray panel, where the two cuts are arranged parallelto each other.

The container may have multiple pairs of cuts arranged in the samefashion or different fashions.

iv. Zipper or Perforated Line for Unlocking the Container

Optionally, the tray and/or lid contains one or more zipper(s) or aperforated line on the front and/or rear of the container. Typically,the zipper is arranged on the tray and/or lid such that it above thecorners of the tray. For example, the extension portion of the fronttray panel, a connecting region above the extension portion and belowthe tab, and/or the rear lid panel includes a zipper or a perforatedline to facilitate the opening of a locked container. In someembodiments, the zipper or perforated line is located on the extensionportion of the front tray panel (see, e.g. FIG. 31A, zipper 1010, FIG.31B, zipper 1010′, and FIGS. 32A and 32B, zipper 1010″) or on the rearlid panel (see, e.g. FIG. 31C, zipper 2010′). FIGS. 31A, 31B, 32A, and32B may be modified to include the zipper in the connecting region 1030,1030′, and 1030″ above the fold line connecting the extension portionand the tab. Although not shown, a zipper can be incorporated on thetray and/or lid of any one of the containers described herein, such ason the extension portion, in the connecting region, and/or on the rearlid panel.

Typically, the zipper is formed by two perforated line(s), such as twoparallel perforated lines. The zipper can have any suitable shape anddimensions. When the zipper is located in the extension portion, itslengths are the distances between a first edge of the extension portionand a second edge of the extension portion in the region of theextension portion in which the zipper is located. As the extensionportion can have a trapezoidal shape, the length of the zipper portionvaries from a first longest length to a second shortest length. Thezipper can include a pull-tab on one end or both ends of the zipper. Forexample, the zipper can include a single pull-tab on one end of thezipper. Alternatively, the zipper can include two pull-tab(s), where afirst pull-tab is on a first end of the zipper and a second pull-tab ison a second end of the zipper. For example, as shown in FIG. 31B, thezipper 1010′ is formed by two perforated lines 1011′ and 1013′ andincludes two semicircular pull-tabs 1012′ and 1014′; a first pull-tab1012′ is located on a first end 1022′ of the zipper and a secondpull-tab 1014′ is located on a second end 1024′ of the zipper. Thepull-tab can have any suitable shape and dimensions as long as a usercan pull on the pull-tab and thereby remove the zipper from thecontainer. Exemplary shapes for the pull-tab are circles (e.g. fullcircle, semicircle, ¾ circle, etc.), triangle, square, rectangle, andpolygons, and combinations thereof, such as semicircles (see, e.g., FIG.31B, 1012 ′ and 1014′) and polygons (see, e.g., FIGS. 32A and 32B, 1012″ and 1014″).

The zipper can include one or more additional cut line(s) on the zipper,such as located on one side of the zipper and/or in the middle of thezipper to facilitate removal of the zipper from the container. Forexample, cut line 1015′ is arranged perpendicularly to each perforatedline 1011′ and 1013′ and located in the middle of the zipper 1010′ suchthat a user can remove the zipper from the extension portion 1312′ bypulling either end of the zipper.

Optionally, the lid or the tray contains only one perforated line on thefront and/or only one perforated line on the rear to allow easy openingof the lid from the tray. The perforated line can be located on thefront of the container, such as anywhere on the extension portion, atthe fold line connecting the extension portion and the tab, at the foldline connecting the extension portion and the front panel, or in theregion connecting the extension portion and the tab. The perforated linecan be located on the rear of the container, such as anywhere on therear lid panel or at the fold line connecting the rear tray panel andthe rear lid panel. For example, although not shown in FIGS. 31B and31C, the perforated line can locate anywhere on the extension portion1312′, at fold line 1315′, at fold line 1313′ (which overlaps withperforated line 1013′), in the connecting region 1030′, on the rear lidpanel 1210′, and/or at fold line 1112′. The perforated line can beincorporated on the tray and/or lid of any one of the containersdescribed herein, such as on the extension portion, at the fold lineconnecting the extension portion and the tab, at the fold lineconnecting the extension portion and the front panel, in the regionconnecting the extension portion and the tab, on the rear lid panel,and/or at the fold line connecting the rear tray panel and the rear lidpanel.

d. Locking Mechanism

The lid and tray are able to be secured in the closed position via oneor more locking mechanisms. The container includes at least one lockingmechanism. Optionally, the container includes two or more lockingmechanisms.

i. Tab in Slit

One locking mechanism includes a slit in in the top panel of the lid anda front tray panel with an extension portion that terminates in one ormore tabs with any suitable geometry that allows the tab to be insertedinto the slit on the lid to lock the lid and tray in the closedposition.

The top panel contains a slit which corresponds to the size and shape ofthe corresponding tab.

The tab can have any suitable size and shape that is configured to fitinside the corresponding slit on the top panel of the lid. Suitable tabsinclude hook tabs, such as a right hook tab, a left hook tab, or adouble hook tab, tuck tabs, and other suitable types of tabs. Exemplarytabs are shown in FIGS. 9A-9F, 23A-23D, and 29 . As shown in FIGS. 9B-9Dand 23B-23D, the hook may be a right hook (314′ in FIG. 9C and 314 ′″ inFIG. 23C) or a left hook (347 in FIG. 9B, 357 in FIG. 9D, 347 ′ in FIG.23B, and 357 ′ in FIG. 23D). As shown in FIG. 9E, the hook may be atwo-sided hook 329, with a right hook 331 a attached to a left hook 331b via a curved connecting portion 333. Exemplary double sided push tabsare illustrated in FIGS. 9A, 9F, 24A and 30 . As shown in FIGS. 9A and24A, the tab can have two flaps (337 a and 337 b in FIG. 9A, and 337 a′and 337 b′ in FIG. 23A) that fit inside two correspondingly shapedslits. As shown in FIG. 29 , the tab 390 can have two flaps, with aright flap 396 a attached to a left flap 396 b via a connecting portion393, which fit into a slit 236.

The slit can be a single cut line having a suitable shape and size toreceive the corresponding tab, such as a curved cut line (convex orconcave), a straight cut line, or other suitable shapes to receive thecorresponding tab. Optionally, one or more additional cut lines arearranged perpendicularly to the slit, such as located on each side ofthe slit, in the middle of the slit, or on each side and the middle ofthe slit. The additional cut lines are configured to facilitate removalof the tabs from the slit. Exemplary slits are shown in FIGS. 9A-9F,23A-23D, and 30 . As shown in FIGS. 9B and 9D, slit 247 may be a singlecut curved line terminated with a straight line on the left end toreceive the left hook tab 347. As shown in FIGS. 9C and 24C, slit 267 isa mirror image of slit 247 to receive the right hook tab 314′. As shownin FIGS. 9A, slits 237 a and 237 b are two rectangular cut outsconfigured to receive the two flaps 337 a and 337 b of the correspondingtab 335. As shown in FIG. 9E, slit 377 is a single curved cut line toreceive the corresponding tab 329. As shown in FIG. 9F, slit 226′ is asingle curved cut line to receive the two corresponding tabs 319 a and319 b. Additional cut lines 227 a and 227 b are arranged perpendicularlyto slit 226′, such as located on each side of the slit and configured tofacilitate removal of the tabs from the slit. As shown in FIG. 29 , slit236 is a single curved cut line to receive the two flaps of tab 390.

Additional cut lines 227′a, 227′b, and 227′c are arrangedperpendicularly to slit 236, such as located on each side and in themiddle of the slit and configured to facilitate removal of the tabs fromthe slit.

ii. Locking Detents

Another locking mechanism includes cooperating pairs of latching memberson the front of the lid and the tray. Optionally, the latching membersare located on the front corners of the lid, located generally at thebottom of the lid and the front corners of the tray, located generallyat the top of the tray. In other embodiments the latching members arelocated on the lower portion of the front lid panel and adjacent to arecessed portion of the front lid panel while the corresponding latchingmembers on the tray are protrude from the sides of an extension portionattached to the front tray panel.

1. Perpendicular Detents

In some embodiments, each latching member on the lid is perpendicular toa corresponding latching member on the tray. For example, each of thelatching members on the lid can be a single layer or double layer tab,which function as a detent, that is in the same plane as one of the sidepanels of the lid and protrudes outwardly from the lid, and each of thecorresponding latching members on the tray can be can be a single layeror double layer tab, which function as a detent, that is in the sameplane as front panel of the lid and protrudes outwardly from the lid.

In one embodiment, the tray contains a first pair of tabs, whichfunction as a pair of detents, protruding from the upper corners of thefront tray panel, and the lid contains a second pair of tabs, whichfunction as a pair of detents, that are aligned perpendicular to thefirst pair of detents. The second pair of detents contains one detentprotruding from the lower corner of one side lid panel and the seconddetent protruding from the lower corner of the second side lid panel.The first and second pairs of detents are configured to contact eachother when the container is in the closed position, such that the firstpair of detents lies on top of the second pair of detents.

In another embodiment, the tray contains a first pair of tabs, whichfunction as a pair of detents, protruding from the upper corner of eachof the side tray panels, and the lid contains a second pair of tabs,which function as a pair of detents, that are aligned perpendicular tothe first pair of detents and protrude from the lower corners of thefront lid panel. The first pair of detents contains one detentprotruding from the upper corner of one side tray panel and the seconddetent protruding from the upper corner of the second side tray panel.The first and second pairs of detents are configured to contact eachother when the container is in the closed position, such that the firstpair of detents lies on top of the second pair of detents.

2. Detents in the Lid and Tray that Interlock Along the Front of theContainer

In some embodiments, locking mechanism can include cooperating pairs oflatching members on the front lid panel and their corresponding latchingmembers on and extension portion attached to the front tray panel. Forexample, the tray contains an extension portion that extends from thefront tray panel and includes a first pair of tabs, that function as apair of detents, and protrude from each side of the extension portion,generally located at the bottom of the extension portion (adjacent to ornear the fold line between the front tray panel and the extensionportion), and the lid contains a second pair of tabs, that function as apair of detents, on the front lid panel where each tab is located at anopposite end of the front lid panel and in a recessed portion of thefront lid panel. The second pair of detents on the lid is configured tocontact the first pair of detents on the tray when the container is inthe closed position, such that the first pair of detents mates with andlies above the second pair of detents and locks the container in theclosed position.

II. Paperboard Blank

A paperboard blank is used to form the single use, disposable paperclamshell container described herein.

The blank is formed from a foldable material, such as paper-basedmaterial such as paperboard or corrugated sheet material, although othermaterials may be used if desired. In embodiments utilizing paperboard,the paperboard may be virgin or recycled material, may be coated oruncoated, and may be single-ply or laminated paperboard.

The foldable material may be Folding Box Board (FBB). FBB is achemically and mechanically generated multiply pulp material making itstrong and durable. FBB includes a bleached chemical layer.

The foldable material may be Solid Bleached Sulfate (SBS) Board. Thistype of board is formed by chemically pulping fibers and then bleachingit. The bleached pulp is refined and formed into boxes. SBS boxesgenerally contain white surfaces on the inside and outside of the box.SBS can be coated on only one side (CIS) or on both sides (C2S).

FBB and SBS board are produced from virgin fibers and are generallysuitable for all types of product packaging.

SBS board quality also allows special processes such as embossing &debossing, hot foil stamping or spot UV printing due to its gradequality.

The foldable material may be Natural Kraft or Coated Unbleached Kraft(SUS or CUK). This type of board is made from 100% recyclable materials,and is often used for kraft packaging. When coated with polyethylene(PE) resin, this board can be used to make food packaging of wetstrength. At least 80% of virgin unbleached wood pulp is used to makeCUK. This type of board is strong and durable; the stiffness leads tohigh resistance to tearing making the board long-lasting. The printingquality of the board can be improved by coating the surface with a thinlayer of kaolin clay.

The foldable material may be from about 0.012 inch to about 0.024 inchthick, although it may have any suitable thickness.

In some embodiments, the foldable material may be solid bleached sulfate(SBS) with ½ mil low density polyethylene (LDPE), while in otherembodiments the foldable material may be SBS with ¾ mil LDPE, while instill yet other embodiments, any other suitable foldable material may beused.

Different types of food grade paperboard may be used to form the blankand ultimately the container. The paperboard is optionally ovenablepaperboard suitable for use in conventional and microwave ovens.

The paperboard may be coated with a suitable food grade material toreduce leakage, such as a polyester resin film. Optionally, the side ofthe paperboard blank that forms the inside surface of the resulting trayis coated with a liquid impervious polymer film. Optionally, the blankis coated on one side, which will serve as the inside surface of theresulting container, with a clay-coat, which is cured with a UV orelectron beam varnish.

The paperboard blank contains a plurality of score lines that define acentral polygonal bottom panel (referred to as the tray portion), whichforms the bottom of the tray when it is assembled, and a centralpolygonal top panel (referred to as the lid portion) that forms the lidwhen the blank is assembled. The lid portion and the tray portion areconnected via a fold line.

a. Tray Portion of the Blank

Some of the score lines on the tray portion form a plurality of bottomedges, defining the bottom panel and also serve as the bottom edge ofeach of the tray panels. Four tray panels extend outward from the bottompanel. The bottom edges can be folded to assemble the tray panels, suchthat they are angled away from the bottom panel at an angle greater than90° when the tray is assembled.

In some embodiments, the bottom panel is in the shape of a rectangle. Insome embodiments, the bottom panel is in the shape of a square. However,the bottom panel may be in the shape of other polygons.

In the tray, each tray panel is attached to an adjacent tray panel via apair of triangular-shaped gusset panels. In a pair of gusset panels,each gusset panel shares a side with the other gusset panel, and thisshared side also serves as a first fold line. Thus, each gusset panel isattached to the other gusset panel in the pair via the first fold line.Each gusset panel in the pair is also attached to the adjacent traypanel (which can be a side tray panel, a front tray panel, or a reartray panel) via a second fold line. The second fold line is at asuitable angle for forming a tray with the tray panels, each of whichextend from the bottom panel, at an angle of greater than 90°, typicallyat an angle ranging from 100° to 120° when the tray is assembled.

b. Lid Portion of the Blank

Some of the score lines on the lid portion form a plurality of topedges, defining the top panel and also as the top edge of an each of thelid panels. Four lid panels extend outward from the top panel. The topedges can be folded to assemble the lid panels, such that they areangled away from the top at an angle greater than 90° when the lid isassembled.

In some embodiments, the top panel is in the shape of a rectangle. Insome embodiments, the top panel is in the shape of a square. However,the top panel may be in the shape of other polygons. Further, the lidcan be substantially flat or curved. Optionally, the lid is curved, suchas in the shape of a dome.

Each lid panel is typically attached to an adjacent lid panel via a gluetab. The glue tabs are typically attached to the front lid panel or rearlid panel via a fold line. In this embodiment, the glue tabs areadjacent to but disconnected from the adjacent side panel.Alternatively, the glue tabs can be attached to each of the side panelsvia a fold line. In this embodiment, the glue tabs are adjacent to butdisconnected from the front lid panel or rear lid panel. The fold lineis at a suitable angle for forming a tray with the adjacent lid panels,each of which extend from the bottom panel, at an angle of greater than90°, typically at an angle ranging from 100° to 120° when the tray isassembled.

The front lid panel is defined by a top edge, formed by the fold linebetween the top panel and the front lid panel, two side edges formedwhen the pair of glue tabs are attached to the front lid panel, and alower border.

In some embodiments, the front lid panel includes a recessed portion.The recessed portion can be configured to facilitate alignment of acorresponding extension portion on the tray and/or locking of the lidand the tray in the closed position. In embodiments in which the frontlid panel includes a recessed portion, the front lid panel is defined bya top edge, formed by the fold line between the top panel and the frontlid panel, two side edges formed when the pair of glue tabs are attachedto the front lid panel, and a recessed portion defined by an upperborder, two side borders, a first portion of the lower border, and asecond portion of the lower border, where each portion of the lowerborder is connected to one of the side borders. Each portion of thelower border is substantially parallel to the upper border. Typicallythe upper and lower borders are straight. The side borders can bestraight or curved. Optionally, the front lid panel contains two frontcorners, where each corner is located on one side of the recessedportion (see, e.g. FIG. 29, 283 a″ and 283 b″). The front corners areconfigured such that when the container is in the closed position, thefront corners lie on top of a portion of the front tray panel (see, e.g.FIGS. 30B and 30C, 283 a″ and 283 b″).

Optionally, the side borders are curved and include tabs that protrudeinwardly. These tabs can function as lid detents that interconnect andlock with corresponding tray detents.

In some embodiments, the pair of glue tabs that are attached to thefront lid panel contain a tab portion. Optionally, the edge of eachadjacent side panels that is proximal to the front lid panel alsocontains a correspondingly shaped tab portion. The tab portions on thefront lid panel can align with a correspondingly shaped tab portions onthe adjacent side lid panels to form a pair of bi-layer or double-plylid detents, which mate with the corresponding tray detents to serve asa locking mechanism when the container is in the closed position.Optionally, either the lid side panels or the front lid panel do notcontain tab portions. In this embodiment, the lid detents are singlelayer or single-ply.

As shown in FIG. 3 , various fold lines, e.g., 223′ and 225′, can becurved. Alternatively, as shown in FIG. 1 , the same fold lines, e.g.223 and 225, can be straight. Although the curved fold lines are shownon the lid portion 200′, similar curved fold lines can also be presenton the tray portion 300′. Whether a given fold line is curved orstraight depends on the desired geometry of the resulting container.

c. Locking Mechanism: Belt Formed from Extension Portion with Tab

The front tray panel typically includes an extension portion, which isconnected to the front panel along a fold line. The extension portionextends beyond the height of the side tray panels, when the tray isassembled. The extension portion terminates with a tab of any suitableshape, such as a hook tab or tuck tab. The extension portion is foldablealong the fold line such that it lies in a different plane than theplane of the front tray panel. When folded, the extension portiontypically lies in a first plane that is parallel to the plane of thefront lid panel, while the tab lies in a plane that is substantiallyparallel to the top panel of the lid. These planes intersect at an anglegreater than 90°.

The extension portion may include a second fold line, which aligns withthe edge formed by the fold line between the front lid panel and the toplid panel when the tray is assembled. The second fold line allows thetab to be folded such that it is substantially parallel to the top lidpanel and inserts in a slit on the top lid panel to secure the containerin the closed and locked position. The extension portion may include twoor more alignment fold lines (such as 2, 3, 4, 5, or more alignment foldlines) adjacent to each other to allow for variability in the shape ofthe container when it is filled with its contents. Having at least twoalignment fold lines allows for a container to be filled such that itslid bulges, yet the container can be secured in the closed and lockedposition by inserting the tab attached to the extension portion into theslit on the lid. Optionally, the extension portion includes twoperforated lines (1011′″ and 1013′″ in FIG. 2B and lines 1011″″ and1013″″ in FIG. 2C) that form a zipper (see, e.g., FIG. 2B, zipper 1010′″and FIG. 2C, zipper 1010″″) and/or a single perforated line (not shownin figures). Optionally, the zipper includes a pull-tab on one end orboth ends of the zipper. For example, the zipper includes a singlepull-tab on one end of the zipper. Alternatively, the zipper includestwo pull-tabs, where a first pull-tab is on a first end and a secondpull-tab is on a second end of the zipper (see, e.g., FIG. 2B, 1012 ′″and 1014′″).

In some embodiments, the extension portion includes a pair of tabs onthe corners of the extension portion, generally located at the bottom ofthe extension portion. The length between the pair of tabs is longerthan the fold line connecting the extension portion and the front traypanel. In the closed position, the extension portion and its pair oftabs lies on top of a portion of the front lid panel. The length betweenthe pair of tabs is shorter than the fold line between the front lidpanel and the top lid panel. The pair of tabs can serve as tray detents,which provide an additional locking mechanism for the container in itsclosed position.

The front lid panel may include a corresponding pair of tabs in therecessed portion of the front lid panel. The pair of tabs on the frontlid panel can serve as lid detents that mate with the tray detentslocated on the extension portion of the front tray panel. In someembodiments, the lid detents and tray detents are configured to contacteach other when the container is in the closed position, such that theinside surface of the lid detents contacts the outside surface of thefront tray panel and the lid detents lie on top of a portion of theoutside surface of the front tray panel and above the lid detents.

Examples

A. Clamshell Containers with Rectangular Bottom and Top Panels

FIG. 1 illustrates a plan view of a blank 100 that may be used to forman exemplary clamshell carton with a rectangular tray and lid, such asillustrated in FIGS. 5A-5C. The blank 100 may include a first surface110 and a second surface on an opposing side of the blank. The firstsurface 110 may define an outer surface when the blank is formed into aclamshell carton, and the second surface may define an inside surface.

The blank 100 may comprise a number of panels interconnected by foldlines or other suitable lines of weakening. Generally, the blank 100 mayinclude a lid portion 200 and a tray portion 300 which may be connectedby a fold line 112. The lid portion 200 and the tray portion 300 may beassembled to respectively form a lid 2000 and a tray 3000.

Optionally, the fold line 112 connecting the lid portion and trayportion is broken or open in one or more locations, such as in the formor a slit or perforations, which helps prevent buckling of the containerwhen it is formed.

The lid portion 200 contains a top panel 220 in the center of the lidportion, and the top panel is foldably connected to four lid panels,with one on each side of the top panel. The four lid panels are thefront lid panel 210, the two side lid panels 222, 224 and the rear lidpanel 230.

More specifically, the lid portion 200 contains a front lid panel 210foldably connected along fold line 211 to a top panel 220. The top panel220 is foldably connected along fold line 221 to rear lid panel 230.Side lid panels 222, 224 are respectively foldably connected to the toppanel 220 along respective fold lines 223, 225. Optionally, the rear lidpanel is modified to include a perforated line and/or a zipper, such asthe zipper on the rear lid panel as shown in FIG. 32C, zipper 2010′.

The top panel 220 also contains a slit 226 configured to receive acorresponding tab that extends from the tray portion 300.

The tray portion 300 contains a bottom panel 320 in the center of thetray portion, and the bottom panel is foldably connected to four traypanels, with one on each side of the bottom panel. The four tray panelsare the front tray panel 310, the two side tray panels 322, 324 and therear tray panel 330.

The tray portion 300 includes a rear tray panel 330 that is foldablyconnected to the rear lid panel 230 along fold line 112. The rear traypanel 330 is foldably connected along fold line 321 to a bottom panel320. The bottom panel 320 is foldably connected along fold line 311 to afront tray panel 310. Further, side tray panels 322, 324 arerespectively foldably connected to the bottom panel 320 along respectivefold lines 323, 325.

The front tray panel may include an extension portion 312, which extendsbeyond the height of the side tray panels, when the tray is assembled.The extension portion 312 is foldably connected to the front panel alonga fold line 313. The extension portion includes a second fold line 315(also referred to as an alignment fold line), which aligns with foldline 211 on the lid, when the container is in the closed position.Optionally, the extension portion contains two or more alignment foldlines, 315 a, 315 b, that are adjacent to each other to allow forvariability in the shape of the container when it is filled with itscontents. Having at least two alignment fold lines allows for acontainer to be filled such that its lid bulges, yet the container canbe secured in the closed position, by inserting the tab on the extensionportion into a slit on the lid. The extension portion 312 terminates ina tab of any suitable shape, such as a hook tab 314 (see FIG. 1 ) ortuck tabs 319 a and 319 b (see FIG. 3 ), which fit in the slit 226 onthe top panel of the lid to secure the container in the closed position.Optionally, the extension portion of the front tray panel includes aperforated line or a zipper, such as zipper 1010′ shown in FIG. 31B, tofacilitate opening a closed and locked container.

In the tray portion, gussets 340 a and 340 b attach the rear tray panel330 to the respective adjacent side panel 324, 322. Gussets 350 a and350 b attach the front tray panel 310 to the respective adjacent sidepanel 324, 322. Gussets 340 a, 340 b, 350 a, and 350 b are typicallysecured to the outside surface of the respective side panel 322, 324.Optionally, gussets 340 a″, 340 b″ can be secured to the outside surfaceof the rear tray panel 330 (see, e.g. FIG. 6C). Alternatively, gussets340 a, 340 b can be folded inwardly and secured to the inside surface ofthe side panels 322, 324 or the rear tray panel 330 (not shown inFigures).

Optionally, gussets 350 a and 350 b are formed from a gusset panel 352that includes a tab portion 316 that aligns with a correspondinglyshaped tab portion 318 on the front tray panel 310 and forms a pair oftray detents 360 a″, 360 b″, i.e. a portion of a locking mechanism (seeFIGS. 6A-6C). In this embodiment, the tray detents are two-ply orbi-layered. Alternatively, either the gusset panel 352 or the front traypanel 310 does not include a tab portion 316 or 318, respectively. Inthis embodiment, the tray detents 360 a, 360 b, i.e. a portion of alocking mechanism, are single layer or single-ply (see e.g., FIGS.5A-5C).

Each gusset 340 a, 340 b, 350 a, and 350 b in the tray is formed fromoverlapping gusset panels 342 a and 342 b connected by a fold line 345that is substantially in the center between the two gusset panels. Foldline 345 is an oblique line and intersects with side fold lines 343 aand 343 b. Side fold lines 343 a and 343 b connect the respective gussetpanels to the adjacent side panel with sealing portions of the gussetpanels extending the full depth of the side panels.

Optionally, the paperboard blank contains one gusset panel with acut-out portion 372, 376 in one or more of the pairs of gusset panels(e.g., one panel in the pair containing gusset panels 342 a, 342 b andone panel in the pair containing gusset panels 352, 354). The cut-outportion 372, 376 is located in the gusset panel that is closest to thepanel to which it is being attached. By including a cut-out, adhesive isalso placed on a portion, typically the upper portion of the outergusset, thereby directly sealing the outer gusset to the side panel aswell. Optionally, the portion of the side panel (or, alternatively, rearor front panel) to which the gusset is adhering contains a debossed orembossed raised portion 370, 370′ that has a corresponding shape to fitinside the cut-out portion 372, 376, and thereby facilitate a secureattachment of the gusset to the adjacent tray panel (see, e.g. FIGS. 8Aand 8B).

In the lid portion, a glue tab 212 a (e.g., a flap for being attached,such as with adhesive material) may be connected to the front lid panel210 along fold line 213 a. The glue tab 212 a may abut, but remainseparate from (e.g., disconnected from), the adjacent side lid panel 210due to a cut line 217 being positioned therebetween. Similarly, glue tab214 a is connected along fold line 217 a to rear lid panel 230. Alsosimilarly, glue tab 214 a may abut, but remain separate from theadjacent side lid panel 224 along cut line 219 a. A mirror image of thisglue tab configuration may be formed along the opposite side of theblank 100 where glue tabs 212 b and 214 b (e.g., attachment flaps) areconnected along fold lines 213 b and 217 b, respectively, to front lidpanel 210 and rear lid panel 230, respectively. Similarly, glue tabs 212b and 214 b extend until but are separate from the adjacent side lidpanel 222 along respective cut lines 215 b and 219 b.

The pair of glue tabs 212 a and 212 b, which are attached to the frontlid panel 210, optionally contain a tab portion 216 a and 216 b. The tabportion 216 a and 216 b can align with a correspondingly shaped tabportion 218 a and 218 b on the adjacent side panel 222, 224 to form apair of bi-layer or double-ply lid detents 260 a, 260 b, which mate withthe corresponding tray detents 360 a, 360 b (or 360 a″, 360 b″) to serveas a locking mechanism when the container is in the closed position.

In some embodiments, neither the side lid panels nor the front lid panelcontain a tab portion. In these embodiments, the lid does not includedetents to interlock with corresponding detents on the tray. Optionally,either the side lid panels or the front lid panel do not contain tabportions. In this embodiment, if lid detents are present, the liddetents are single layer or single-ply.

Similarly, glue tab 214 a is connected along fold line 217 a to rear lidpanel 230. Also similarly, glue tab 214 a may abut, but remain separatefrom the adjacent side lid panel 224 along cut line 219 a. A mirrorimage of this glue tab configuration may be formed along the oppositeside of the blank 100 where glue tabs 212 b and 214 b (e.g., attachmentflaps) are connected along fold lines 213 b and 217 b, respectively, tofront lid panel 210 and rear lid panel 230, respectively. Similarly,glue tabs 212 b and 214 b extend until but are separate from theadjacent side lid panel 222 along respective cut lines 215 b and 219 b.

The glue tabs are configured to attach the front lid panel and rear lidpanel to each of the side lid panels to form the lid. In one embodiment,the side lid panels 222, 224, front lid panel 210, and rear lid panel230 of the lid portion 200 are folded toward one another, the glue tabs212 a, 212 b, 214 a, 214 b fold inwardly to overlie partially the innersurfaces of their respective adjacent side panels, 222 and 224, to whichthey can be attached via an adhesive (or other material or method) toform the lid 2000. Alternatively, the glue tabs may be adhesively orotherwise attached to the exterior surfaces of the respective sidepanels.

FIG. 15 illustrates a plan view of a blank 100″ that may be used to formanother exemplary clamshell carton with a rectangular tray and lid, suchas illustrated in FIGS. 17A-17C and 18A-18C. The reference numbers andcorresponding descriptions above with respect to the exemplary blank forforming a rectangular clamshell container in FIG. 1 generally apply tothe blank illustrated in FIG. 15 and the resulting clamshell container.However, the blank depicted in FIG. 1 includes interlocking detents thatalign substantially perpendicular to each other to lock the resultingcontainer in closed position, while the blank depicted in FIG. 15contains interlocking detents that align nearly parallel, yetintersecting planes at less than 90°, and typically between 0° and 10°,between 0° and 5° or less than 5°, such that one set of detents lies ontop of the other to lock the resulting container in the closed position.Differences between blank 100″ in FIG. 15 with respect to blank 100 inFIG. 1 and the resulting clamshell containers are described below.

FIG. 15 shows a different configuration than shown in FIG. 1 for thelocking mechanism that utilizes interlocking lid detents and traydetents.

As shown in FIG. 15 , the extension portion 312″ includes a pair of tabs382 a and 382 b on the opposite corners of the extension portion,generally located at the bottom of the extension portion 312″ near thefold line 313″, which connects the front tray panel 310″ to theextension portion 312″. The tabs function as a pair of tray detents andprotrude beyond the fold line 313″. The distance (d₁) between the tabs382 a and 382 b is longer than the length (L₁) of the fold line 313″.When the container is assembled and placed in the locked position, thepair of tabs 382 a and 382 b function as tray detents that lie on top ofthe front lid panel 210″ and in a plane that is nearly parallel to, butintersects with, the plane of the front lid panel 210″.

The front lid panel 210″ includes a corresponding pair of tabs 282 a and282 b inwardly protruding along a portion of the upper border 281 of thefront lid panel 210″.

As shown in FIG. 15 , the front lid panel 210′″ includes a recessedportion 285, defined by an upper border 281, two side borders 287 a and287 b, and a first and a second portion of a lower border 293″a and293″b. The height of the front lid panel (H_(L)) is measured from theupper border 281′ of the recessed portion to the fold line 211″ betweenthe front lid panel 210″ and the top panel 220″.

The pair of tabs 282 a and 282 b on the front lid panel 210″ areconfigured to function as lid detents when the container is assembledand in the locked position, such that the lid detents 282 a and 282 binterlock and mate with the tray detents 382 a and 382 b when thecontainer is in the closed position. The lid detents 282 a and 282 b andtray detents 382 a and 382 b are configured to contact each other whenthe container is in the closed position, such that the inside surface ofthe lid detents contacts the outside surface of the front tray panel andthe lid detents lie on the outer position along the front tray panel(see FIGS. 17B-17C).

Although not illustrated in FIG. 15 , the tab 314″ and correspondingslit 226″ can be modified to have any other suitable configuration, suchas illustrated in FIGS. 23A-24D and 24A-24C, 24D, and 24E.

The lid and/or tray optionally include one or more vents, one or morezippers, and/or a perforated line. For example, the blank 100″ shown inFIG. 15 can be modified to include a zipper on the extension portion ofthe front tray panel, in the connecting region of the front tray panel,and/or on the rear lid panel, such as the zipper as shown in FIG. 31B,zipper 1010′ and FIG. 31C, zipper 2010′. The vents can be formed from asingle cut line or more than one cut line on one or more panels.

The vents can be formed from relief cuts on the fold line of thecontainer to allow for heat and steam to escape from the closedcontainer, such as when hot food is enclosed therein. As shown in FIG.16 , two pairs of relief cuts 291 a and 391 a, 291 b and 391 b may beincluded on the blank 100″. Relief cuts 291 a, 291 b are located on therear lid panel 230″ and relief cuts 391 a, 391 b are located on the reartray panel 330″. Each pair of relief cuts, 291 a and 391 a, 291 b and391 b, forms a V-shape centering on the fold line 112″ that connects thelid portion 200″ and the tray portion 300″. Alternative configurationsof relief cuts may also be present on the blank. For example, more thantwo pairs of relief cuts may be present, or the pairs of relief cuts maybe aligned in a different manner, such as substantially parallel to eachother.

As shown in FIGS. 9A, 9B, 23A, and 23B, the vents can be a single cutline 292 or 292′ in the rear panel. Alternative configurations for thevents may also be present on the blank. For example, more than one ventmay be present on the same panel or different panels.

Alternatively, blanks that may be used to form exemplary clamshellcontainers with a rectangular tray and lid can contain single lockingmechanism involving a belt that extends from one portion of theclamshell container, such as the tray and wraps around part of the otherportion, such as the lid, and is secured thereto, such as by inserting atab into a slot configured to receive and retain the tab.

Exemplary blanks, such as 100′″ and 100′″″, that contain a singlelocking mechanism involving an extension portion are illustrated inFIGS. 18, 28, and 29 . The reference numbers and correspondingdescriptions above with respect to the exemplary rectangular clamshellcontainers in FIG. 1 and FIG. 15 generally apply to the blanks forforming the rectangular clamshell containers without detents in FIGS.18, 28, and 29 , respectively.

A few differences between blank 100 (FIG. 1 ) and blank 100′″ (FIG. 18), and between blank 100″ (FIG. 15 ) and 100′″″ (FIG. 28 ) for formingrectangular clamshell containers are described below.

As shown in FIG. 18 , the upper border of the front tray panel 310′″ isdefined by fold line 313′″ and cut lines 391 a and 391 b, where each ofcut lines 391 a and 391 b is located on an opposite end of fold line313′″. The upper border of the front lid panel 210′″ is defined by lowerborder cut line 293′″ and with connecting cut lines 297 a and 297 b,which are located on opposite ends of lower border cut line 293′″ andattached via fold lines to each of glue tabs 212 a′″ and 212 b′″.

As shown in FIG. 18 , the front lid panel 210′″ does not contain arecessed portion. However, the blank in FIG. 18 could be modified tocontain a recessed portion 285′, such as illustrated in FIG. 28 .

As shown in FIG. 28 , the front lid panel 210′″″ includes a recessedportion 285′, defined by an upper border 281′, two side borders 287′aand 287′b, and a first and a second portion of a lower border 293″″a and293′″″b. The height of the front lid panel (H_(L)) can be measured fromthe upper border 281′ of the recessed portion 285′ to the fold line211′″″ between the front lid panel 210′″″ and the top panel 220′″″.

Although not illustrated in FIGS. 18 and 28 , the blank 100′″ and blank100′″″ can be modified to include a perforated line and/or a zipper onthe tray panel and/or lid panel of the blank (e.g., on the extensionportion of the front tray panel, in the connecting region of the fronttray panel, and/or on the rear lid panel), such as the zipper as shownin FIG. 31B (see, e.g. zipper 1010′) and/or in FIG. 31C (see, e.g.zipper 2010′).

Although not illustrated in FIGS. 1, 15, 18, and 28 , the extensionportion and hook, and the corresponding slit on the top lid panel may bereplaced by any shape and configuration. Exemplary alternative shapesfor the tab, extension portion, and slit are shown in FIGS. 9A-9F and 29.

B. Clamshell Containers with Square Bottom and Top Panels

FIG. 3 illustrates a plan view of a blank 100′ which may be used to forman exemplary clamshell carton with a square tray and lid, such asillustrated in FIGS. 4A-4C. The blank 100′ may include a first surface110′ and a second surface on an opposing side of the blank. The firstsurface 110′ may define an outer surface when the blank is formed into aclamshell carton, and the second surface may define an inside surface.

The reference numbers and corresponding descriptions above with respectto the exemplary rectangular clamshell container generally apply to theblank for forming a square-shaped clamshell container and the resultingclamshell container. However, the proportions and angles are different.Thus the same reference numbers are used in FIG. 3 , however, they aredenoted with a prime symbol, e.g. side lid panels 224′ and 222′.

A few differences between the blank for forming the rectangularclamshell and the blank for forming the square-shaped clamshell aredescribed below.

FIG. 3 shows a different configuration than shown in FIG. 1 for thelocking mechanism that utilizes a slit on the top panel. Although notillustrated in FIG. 3 , the locking mechanism for the square-shaped clamshell can have the same configuration as illustrated in FIG. 1 , i.e.slit 226 and hook 314 at the end of the extension portion 312. As shownin FIG. 3 , the locking mechanism includes two tabs 319 a and 319 battached to each other via a connecting portion 317. The connectingportion can have any suitable geometry to attach the tabs to each other,such as curved or straight. As shown in FIG. 3 , the connecting portion317 can be substantially straight. The top panel 220′ contains a slit226′ configured to receive corresponding tabs 319 a and 319 b thatextend from the extension portion 312′ of the front panel 310′ of thetray 300′. The slit 226′ can be a single cut line having a suitableshape and size to receive the tabs 319 a and 319 b. Optionally, one ormore additional cut lines 227 a and 227 b are arranged perpendicularlyto the slit, such as located on each side of the slit and configured tofacilitate removal of the tabs from the slit.

Additionally, as shown in FIG. 3 , the tab portions 216 a′ and 216 b′protrude from each of the respective side panels 224′ and 222′ and arenot in contact with the adjacent glue tab 212 a′ and 212 b′. The lidassembles as described above with respect to the rectangular container,with the glue tabs 212 a′ and 212 b′ connecting to the adjacent sidepanel 224′ and 222′, respectively, and each of the tab portions 216 a′and 216 b′ of the glue tabs aligning with a correspondingly shaped tabportion 218 a′ and 218 b′ on the adjacent side panel 222′, 224′ to formbi-layer or double-ply lid detents 260 a′, 260 b. When the container isin the closed position, the lid detents 260 a′, 260 b′ are located belowthe corresponding tray detents 360 a′, 360 b′. The tray detents 360 a′,360 b′ secure the lid detents 260 a′, 260 b′ in place, thereby servingas a locking mechanism, which prevents the lid from opening without theuse of force to push the detents out of the locked position.

As shown in FIG. 3 , various fold lines, e.g., 223′ and 225′, can thecurved. For example, in FIG. 3 , each of the fold lines between the sidelid panels 222′, 224′ (e.g., the side lid panels) and the top panel 220′curve inwardly toward the top panel 220′. As shown in FIGS. 4A and 4B,when the lid is assembled the side lid panels 224′ and 222′ curveinwardly, i.e. are concave.

Alternatively, as shown in FIG. 1 , the same fold lines, e.g. 223 and225, can be straight. Whether a given fold line is curved or straightdepends on the desired geometry of the resulting container. When theblank includes straight fold lines, such as 223 and 225, the resultingcontainer has substantially flat side lid panels, 224″ and 222″ asdepicted in FIGS. 7A and 7B (222″ is not visible in these figures).

Alternatively, blanks that may be used to form exemplary clamshellcontainers with a square tray and lid can contain single lockingmechanism involving a belt that extends from one portion of theclamshell container, such as the tray and wraps around part of the otherportion, such as the lid, and is secured thereto, such as by inserting atab into a slot configured to receive and retain the tab.

An exemplary blank, such as 100″″, that contains a single lockingmechanism involving an extension portion is illustrated in FIG. 20 . Thereference numbers and corresponding descriptions above with respect tothe exemplary rectangular clamshell container in FIG. 3 generally applyto the blanks for forming the rectangular clamshell containers withoutdetents, such as illustrated in FIG. 20 .

A few differences between blank 100′ (FIG. 3 ) and blank 100″″ (FIG. 20) for forming square clamshell containers are described below.

As shown in FIG. 20 , the upper border of the front tray panel 310″″ isdefined by fold line 313″″ and cut lines 391 a′ and 391 b′, where eachof the cut lines 391 a′ and 391 b′ is located on an opposite end of foldline 313″″. The border of the front lid panel 210″″ is defined by lowerborder 293′″ and connecting cut lines 297 a′ and 297 b′, which arelocated on opposite ends of the lower border 293′″ and attached via foldlines 213 b″″ and 213 a″″ to each of the glue tabs 212 a″″ and 212 b″″.

Although not illustrated in FIGS. 3 and 20 , blank 100′ and blank 100″″can be modified to include a perforated line and/or a zipper on theextension portion of the front tray panel, in the connecting region ofthe front tray panel, and/or on the rear lid panel, such as the zipperas shown in FIG. 2B or 2C, zipper 1010′″ or 1010″″.

Although not illustrated in FIG. 21 , the extension portion and hook,and the corresponding slit on the top lid panel may be replaced by anyshape and configuration. Exemplary alternative shapes for the tab,extension portion, and slit are shown in FIGS. 9A-9F, 24A-24D, 25A-25D,and 30 .

Those skilled in the art will recognize, or be able to ascertain usingno more than routine experimentation, many equivalents to the specificembodiments of the invention described herein. Such equivalents areintended to be encompassed by the following claims.

1. A clamshell container for food storage comprising: a tray and a lid,wherein the lid is hingedly attached to the tray and moveable between anopen position and a closed position, wherein the lid comprises a toppanel comprising a slit, wherein the tray is liquid tight.
 2. Theclamshell container of claim 1, wherein the tray comprises a front traypanel, with an extension portion attached thereto, wherein the extensionportion terminates in a tab, and wherein the tab is configured to fit inthe slit when the container is in the closed position.
 3. The clamshellcontainer of claim 1, wherein the extension portion lays on top of aportion of the front lid panel when the container is in a lockedposition. 4-5. (canceled)
 6. The clamshell container of claim 2, whereinthe tab is a right hook tab, a left hook tab, a double-sided hook tab,or a tuck tab.
 7. The clamshell container of claim 1, wherein the traycomprises a bottom panel and four tray panels, wherein the four traypanels consist of the front tray panel, a rear tray panel, and two sidetray panels; wherein each of the tray panels is attached to one side ofthe bottom panel and protrudes upwards from the bottom panel; whereinthe lid further comprises four lid panels, consisting of a front lidpanel, a rear lid panel and two side lid panels; wherein each of the lidpanels is attached to one side of the top panel and protrudes downwardsfrom the top panel.
 8. The clamshell container of claim 7, wherein eachof the tray panels is attached to the adjacent tray panel via a foldedgusset, wherein each gusset is secured to one of the tray panels.
 9. Theclamshell container of claim 7, wherein each of the lid panels isattached to the adjacent lid panel via a glue tab, wherein the glue tabis secured to one of the lid panels.
 10. The clamshell container ofclaim 1, wherein the front lid panel further comprises a recessedportion.
 11. The clamshell container of claim 10, wherein when thecontainer is in the closed position, the extension portion of the traylies on top of the recessed portion and on top of a portion of the frontlid panel.
 12. The clamshell container of claim 10, wherein the frontlid panel further comprises two front corners, wherein each corner isone side of the recessed portion, and wherein when the container is inthe closed position, the front corners lie on top of a portion of thefront tray panel.
 13. The clamshell container of claim 1, wherein thecontainer further comprises one or more openings for viewing thecontents in the container, and wherein the one or more openings arelocated in the top panel, one or more of the lid panels, or one or moreof the tray panels, or in a combination thereof.
 14. (canceled)
 15. Theclamshell container of claim 1, wherein the top panel, one or more ofthe lid panels, or one or more of the tray panels, or a combinationthereof further comprises one or more vents for releasing heat and/orsteam from the container.
 16. The clamshell container of claim 1,wherein the tray further comprises a first pair of detents protrudingfrom the front tray panel, and wherein the lid further comprises asecond pair of detents that are configured to contact and interlock withthe first pair of detents such that the first pair of detents lies ontop of the second pair of detents when the container is in the closedposition. 17-23. (canceled)
 24. The clamshell container of claim 1,wherein the front lid panel further comprises a recessed portion,wherein the recessed portion is defined by an upper border and two sideborders, wherein each of the side borders protrudes inwardly in the formof a tab that is configured to function as one of the detents of thesecond pair of detents. 25-70. (canceled)
 71. A blank for forming theclamshell container of claim
 1. 72. The blank of claim 71, comprising atray portion and a lid portion foldably connected to each other by afirst fold line, wherein the tray portion comprises a bottom panel; fourtray panels, wherein each of the tray panels shares one side with thebottom panel and is foldably connected to the bottom panel, and whereinthe tray panels consist of the front tray panel, a rear tray panel, afirst side tray panel, and a second side tray panel; and a plurality ofgussets, comprising a first gusset positioned between and connecting thefront tray panel to the first side tray panel, a second gussetpositioned between and connecting the front tray panel to the secondside tray panel, a third gusset positioned between and connecting therear tray panel to the first side tray panel, and a fourth gussetpositioned between and connecting the rear tray panel to the second sidetray panel; and wherein the lid portion comprises: the top panelcomprising the slit; four lid panels, wherein each of the lid panelsshares one side with the top panel and is foldably connected to the toppanel, and wherein the lid panels consist of the front lid panel, a rearlid panel, a first side lid panel, and a second side lid panel; aplurality of glue tabs, comprising a first glue tab positioned betweenthe front lid panel and the first side tray panel, a second glue tabpositioned between the front lid panel and the second side lid panel, athird glue tab positioned between the rear lid panel and the first sidelid panel, and a fourth glue tab positioned between the rear lid paneland the second side lid panel, wherein the glue tabs are configured toattach the front lid panel and the back lid panel to the first side lidpanel and the second side lid panel, respectively.
 73. The blank ofclaim 72, wherein an extension portion is attached to the front traypanel, and wherein the extension portion terminates in a tab, andwherein the tab is configured to fit in the slit when the blank isassembled into a container and the container is in the closed position.74. The blank of claim 71, wherein each gusset is formed from twotriangular shaped gusset panels connected to each other by a second foldline therebetween.
 75. The blank of claim 72, wherein the front lidpanel further comprises a recessed portion.
 76. The clamshell containerof claim 2, wherein the extension portion comprises a single perforatedline or two perforated lines that form a front zipper, and/or whereinthe rear lid comprises a single perforated line or two perforated linesthat form a rear zipper.